CVE-2021-41020Network attack vector

CA certificate replacement via unchecked regeneration URL

Published May 4, 2022 · Updated Oct 25, 2024

Improper access control in Fortinet FortiIsolator 2.3.2 and earlier allows remote authenticated users to regenerate its CA certificate. The certificate-regeneration URL authorizes a nonprivileged account to invoke the CA regeneration operation. Any authenticated nonprivileged account can replace the appliance CA material, disrupting trust in certificates it issues; Fortinet has not disclosed further request-level details.

CVSS severity8.8
High
EPSS probability0.60%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in Fortinet FortiIsolator 2.3.2 and earlier allows remote authenticated users to regenerate its CA certificate. The certificate-regeneration URL authorizes a nonprivileged account to invoke the CA regeneration operation. Any authenticated nonprivileged account can replace the appliance CA material, disrupting trust in certificates it issues; Fortinet has not disclosed further request-level details.

The record

CVE
CVE-2021-41020
Published
May 4, 2022
Updated
Oct 25, 2024
Vendor
Fortinet
Product
FortiIsolator
Classifications
CWE-284, T1553.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 4, 2022CVE publishedPublication date reported by the CVE source.
  2. Oct 25, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=FortiIsolator 2.3.2, 2.3.1, 2.3.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Fortinet · FortiIsolatorversion=FortiIsolator 2.3.2, 2.3.1, 2.3.0

Published CVSS scores

8.8Fortinet, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
6.5NIST NVDAV:N/AC:L/Au:S/C:P/I:P/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-284Improper Access Control
T1553.004Install Root Certificate

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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